The object of the invention is a land vehicle with floating motive power to improve the vehicle of traditional structural type wherein an effective propulsion is available while the vehicle is afloat and a very steep or non-uniform river bank slope can be surmounted without difficulty. It can also pass through the border area between solid ground and water, i.e. mire or bog.
This problem is solved according to the invention in that the propulsion device has a drive wheel with longitudinal ribs, driven to revolve around a horizontal axis, which drive wheel, with the aid of pivot arms at the rear of the vehicle, is height adjustable between a lower position pressed against the ground and an upper position partially immersed in the water.
A drive wheel profiled with longitudinal ribs operates in the sense of a paddle when it is upwardly pivoted state during water travel, whereby a powerful optimum propulsion effect is guaranteed by the adjustable immersion depth, by which only the bottom part of the drive wheel shoves the water away, and it is mounted over essentially the entire breadth of the vehicle, somewhat as a sort of paddle steamer with rear drive. The capacity to cross mire and/or slopes of riverbanks is obtained with this construction such that the drive wheel is pressed downward against the earth with the aid of its pivot arms upon approach to the bank, so that in proportion to the size of the angle of the slope, the drive wheel comes in contact with the ground either first of all or else simultaneously with the front wheels of the vehicle, and in either case an effective support and distribution of the ground support pressure of the vehicle is guaranteed. During movement in mire, the drive wheel which is effective preferably over the breadth of the vehicle serves simultaneously as support and propulsin device.
In a preferred embodiment of the invention, the drive wheel which extends essentially over the entire breadth of the vehicle is longitudinally apportioned, and each wheel half is controllable independently with reference to its speed of rotation and its direction of rotation. The apportioned arrangement of the drive wheel simplifies mounting and maintenance and aids in swinging around and making turns in water. Otherwise, the swinging around in the water can be effected by steering the front wheels.
If the wheel halves are mounted on pivot arms independently from each other or if both of the wheel sections are mounted on one common transverse axle, the vehicle can be easily adapted to the ground irregularities, e.g. by oblique movement along the slope of the bank, so that the vehicle is supported at any moment by the biased pivot arms with the wheel sections being pressed against the ground independent from each other. The wheel arms and drive wheel sections being independent from each other also guarantees a greater maneuverability during flotation.
Besides the application for support of a vehicle during travel on slopes of riverbanks or during balancing on an irregular bottom, the described structure is also basically sound for motor vehicles which use a chain or caterpillar drive with the aid of the drive wheel arrangement and are used for overland travel in mountains during snow and ice, or to produce a propulsion for boggy ground during an almost floating condition, whereby the range of the effect of the selected apportioned drive wheel can be regulated as desired and according to necessity.
Practically, the pivot arms are height adjustable in the rear area of the undercarriage with hydraulic cylinders supported on the undercarriage. The pressure of the drive wheel against the ground can be adjustable with the aid of mechanical or pneumatic spring devices operating on the pivot arms. In this sense, during overland travel of the vehicle, in case of an overrun or spinning of the front wheels, the drive wheels can be connected, so that then a four-wheel drive is available.
In one further proposal of the invention, the drive wheel or wheel sections can be embodied also as drive wheel pairs, on the undercarriage, and if desired with hydrostatic power. By use of hydrostatic power, the motor can be mounted in the best position for land travel and for water travel, e.g. mounted in the front, the midsection, or the rear, according to which structure and which application for the vehicle come most into question.
In a special embodiment of the invention, additional transverse circumferential ribs are arranged on the drive wheel or drive wheel sections, which ribs essentially increase the propulsion effect of the longitudinal ribs while the vehicle is afloat. Thereby the drive wheel body is preferably a hollow body of steel or plastic.
In a preferred embodiment, the drive wheel is embodied in several individually detachably mounted wheel sections, which preferably are embodied as rubber or plastic tires with a strongly defined rib profile, especially a herringbone rib profile. In the top rest position, these wheel sections can project over the rear vehicle end, whereby they work as stabilizer.